REVENUE RECOGNITION AND ACCOUNTS RECEIVABLE - Summary of Accounts Receivable (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total accounts receivable	$ 59,455	$ 60,521
Medicaid
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total accounts receivable	23,321	21,998
Medicare
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total accounts receivable	9,621	11,811
Managed Care
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total accounts receivable	8,052	9,103
Private Pay and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total accounts receivable	$ 18,461	$ 17,609